Dental substances are often provided in devices allowing the substance to be dispensed directly to a desired location, for example on a dental pad or in a patient's mouth. Such dispensing devices typically have a chamber for holding the dental substance, an outlet, and a piston for extruding the substance from the chamber through the outlet.
A variety of dispensing devices are designed for dispensation of relatively high viscosity dental substances, like for example dental filling materials. Some of those dispensing devices are configured for use with an applicator providing an extrusion force that is sufficient for dispensation of high viscosity dental substances. In dentistry several types of manually operated applicators are available which provide leverage for increasing manual forces to provide sufficient extrusion forces. Many applicators are designed as a reusable tool which forms part of a dental practice's basic equipment.
A particular dispensing device often used to store, prepare and dispense a hardenable dental material mixed from a powder and a liquid is the so-called dental capsule in which the mixing of the powder and the liquid is performed within the capsule by shaking the capsule in a shaker.
U.S. Pat. No. 8,893,925 discloses container for mixing and dispensing material. The container comprises a body having a main chamber, a dispensing nozzle, a liquid receptacle and a plunger. The liquid receptacle has a front portion arranged to break away upon pressure being applied by the plunger so that the plunger can traverse the entire length of the body. This enables a charge of material in the main chamber to be entirely dispensed through a frangible wall into the nozzle. The container is particularly envisaged for use in mixing and dispensing of dental materials.
U.S. Pat. No. 8,968,000 discloses a mixing and application capsule for producing and discharging a dental preparation. To prevent a liquid loss, a mixing and application capsule for producing a dental preparation is proposed. The capsule has a capsule body with a mixing chamber for receiving a mixing component and for mixing the dental preparation from the mixing component and a fluid. The capsule further has an outlet opening for discharging the dental preparation. A first plunger body which can be displaced in the capsule body delimits the mixing chamber in the capsule body. The first plunger body has a channel to guide the fluid from a cavity into the mixing chamber and a projection. The capsule has further a second plunger body which can be displaced in the capsule body relative to the first plunger body. The second plunger body has the cavity to receive the fluid. The cavity is configured to receive the projection of the first plunger body.
Such capsules have a variety of advantages as, for example, a relatively long shelf life. However there is a still desire for a capsule with such a long shelf life, which is easy to use and which is nevertheless relatively inexpensive.